Annual mean 17°C · wettest around March · prevailing wind NE
Warmest
30.4 °C
Coldest
8.8 °C
Wettest
34%
Windiest
5.2 m/s
Prevailing
NE
4.3 m/s average
When this place is good five ratings · thirty-six ten-day sections · click a cell to read it
never good
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Every reading
bars actual · line feels-like, °Cchance of rain, %wind speed, m/ssky covered, %
The average temperature in Isumi over the whole year is 17°C. August is the hottest month, with highs of about 30°C; January is the coldest, with lows of about 4°C. Isumi has no sharply defined rainy season: the chance of rain on a given day runs from 10% in January, the driest month, to 23% in March, the wettest. Winds in Isumi are highest in April, averaging 4.2 m/s (15 km/h), and lightest in June, at 3.5 m/s (13 km/h). The prevailing wind is from the NE. The clearest skies in Isumi come in January, when the sky is typically 48% covered; June is the cloudiest month, at 76%.
Month by month Isumi climate by month: average temperatures year round · click a month to read it
Month
High
Low
Feels like
Chance of rain
Cloud
Wind
Being outside
Sun
Walking
January
9°C
4°C
4°C
10%
48%
3.7 m/s
1
0
32
February
10°C
5°C
5°C
11%
55%
4.0 m/s
2
0
34
March
13°C
8°C
9°C
23%
63%
4.0 m/s
15
0
60
April
18°C
13°C
14°C
22%
67%
4.2 m/s
46
1
77
May
21°C
17°C
20°C
20%
71%
3.9 m/s
80
11
68
June
24°C
21°C
25°C
22%
76%
3.5 m/s
71
43
32
July
28°C
25°C
30°C
18%
70%
3.7 m/s
22
55
6
August
30°C
26°C
32°C
16%
68%
3.8 m/s
10
44
2
September
27°C
23°C
28°C
22%
74%
3.6 m/s
43
52
16
October
21°C
17°C
20°C
23%
70%
3.7 m/s
70
18
61
November
17°C
12°C
14°C
17%
61%
3.5 m/s
46
1
79
December
12°C
6°C
7°C
10%
52%
3.5 m/s
6
0
55
High and low are the warmest and coolest of four readings a day — midnight, 6am, noon and 6pm — so a true overnight low can sit a degree or two under them. Chance of rain, cloud and wind are the day’s average; feels-like and the three ratings (each out of 100: Good from 55, Ideal from 80) are read at midday.
Seasons, and the year in short Isumi weather by season
Year round, Isumi has days of about 9°C at their warmest in January, its coolest month, and 30°C in August, its warmest; the coolest hours of the day run from 4°C to 26°C through the year, and the average temperature over the year is 17°C around the clock. Rain is most likely around March and least likely around January. Every figure here is a decade of observations blended into one representative year, so it reads as what this date is usually like, not a forecast for one particular day.
Isumi weather in winterDecember to February
High 10°CLow 5°CRain 10%
Winter in Isumi has typical daily highs of about 10°C and lows of about 5°C, with a 10% chance of rain on a given day.
Isumi weather in springMarch to May
High 17°CLow 13°CRain 22%
Spring in Isumi has typical daily highs of about 17°C and lows of about 13°C, with a 22% chance of rain on a given day.
Isumi weather in summerJune to August
High 27°CLow 24°CRain 19%
Summer in Isumi has typical daily highs of about 27°C and lows of about 24°C, with a 19% chance of rain on a given day.
Isumi weather in autumnSeptember to November
High 22°CLow 17°CRain 20%
Autumn in Isumi has typical daily highs of about 22°C and lows of about 17°C, with a 20% chance of rain on a given day.
When is the rainy season in Isumi?
Isumi has no sharply defined rainy season: the chance of rain on a given day runs from 10% in January, the driest month, to 23% in March, the wettest.
What time of year is Isumi windiest?
Winds in Isumi are highest in April, averaging 4.2 m/s (15 km/h), and lightest in June, at 3.5 m/s (13 km/h). The prevailing wind is from the NE.
What is the average temperature in Isumi year round?
The average temperature in Isumi over the whole year is 17°C. August is the hottest month, with highs of about 30°C; January is the coldest, with lows of about 4°C.